Turbine engines are systems that convert energy within a fuel into mechanical energy (e.g., to move an aircraft, to turn an electrical generator, etc.). Turbine systems traditionally employ various turbine blades designed to extract energy from a high temperature, high pressure gas produced during a combustion reaction within the turbine engine. Often, turbine blades include a core and shell portion, which rotate at very high speeds around a central axis.
The high temperature and high speed operating conditions of turbine blades pose various design challenges for the manufacture of turbine blades. Such challenges include creep failure and failure due to fracture, among others. Creep and fracture may ultimately limit the useable life and the maximum operating temperature of the turbine blade thereby requiring replacement or repair, which may permanently or temporarily render the turbine engine inoperable. Where turbine blades are utilized in large-scale power generation facilities or in the jet turbine market, even limited inoperability may have a substantial impact on production, profitability, and revenue.
Turbine blade designers attempt to reduce creep failure and increase the maximum operating temperature using various methods. Foremost, turbine blades may include increased cross-sectional areas to reduce creep. Moreover, turbine blades may include various cooling passageways extending outward to a leading edge of the turbine blade to increase the maximum operating temperature of the turbine blade. Such passageways may facilitate emission of a fluid (e.g., air) that flows along the outer surface thereby further increasing the maximum operating temperature of the turbine blade.